The invention concerns a device for presenting information near the eyes having a holder designed to be worn on the head of a user, preferably as a head covering or eyeglasses, and having a monocular display unit disposed on the holder, positioned, when in use, in a peripheral visual field range of a first eye of the user.
There are known display units to be worn on the head, provided with a display unit for stationary use and, apart from being heavy, have disadvantages regarding the possibility of an undisturbed observation of the vicinity as well. Moreover, display systems are mainly known in the military field, which project, using expensive technology, important information for the user, a pilot for example, into the field of view, wherein the power supply usually plays an insignificant role.
Based on this, the invention assumes the objective of designing the device known in the prior art in such a manner that the information presentation can take place ergonomically in a compact mobile display unit, having a low production costs without particularly limiting the user in his activities.
To attain this objective, the characteristic combinations disclosed in claim 1 or 8, respectively, are suggested. Advantageous designs and further developments of the invention result from the dependent claims.
The intention of the invention is to adjust the display to the ambient brightness and thereby to optimize the readability. Correspondingly, in accordance with a first aspect of the invention, it is suggested that a light collecting unit that can be loaded with ambient light is disposed on the holder, and that the light collecting unit is coupled with the display unit in such a way that the ambient light is used for the illumination thereof. With this, a bright and contrast-rich display can be realized without costly energy sources, whereby simple manufacturing and ergonomic use, as well as an adaptive adjustment to the ambient light intensity, are also made possible.
Advantageously, the light collecting unit comprises a light conductor structure which receives the ambient light through a preferably upward-facing entry surface and emits the light onto an exit surface connected, or optically coupled, to the display unit. In this manner, a simple automatic contrast control, dependent on the ambient brightness, is possible.
A further improvement is made possible in that the light collecting unit contains an excitable fluorescent or phosphorescent coloring for illumination by means of captured ambient light, preferably within the yellow to green wavelength range. In this way the ambient light can be homogenized independently of the input direction and displaced in the wavelength to a preferred contrast color, wherein UV components are then also usable for the illumination.
A further advantageous possibility for adaptive contrast control exists in the light collector unit having a solar cell charged by means of ambient light for powering the display illumination, or a self-lighting display unit in accordance with the ambient light intensity. Here the output current of the solar cell is used directly for the generation of light for the display unit.
It is basically also possible for the display unit to comprise an auxiliary lighting source, powered by means of a battery, a storage capacitor and/or a solar cell, preferably coupled via the light conductor structure. In this case, a preferably short demand-driven activation of the energy source occurs, such that a long operating time is obtained without involving the user. In this context, it is also beneficial if the connectable light source is adjusted to the display unit's wavelength or light color obtained by the light collecting unit.
Advantageously, the light collecting unit is equipped to penetrate the information-giving display surface of the display unit with transmitted light or irradiate it with incident light, so that a good readability is ensured for any conditions. With this, it is especially beneficial when the display unit comprises a LCD-module, such that, with a compact construction, complex information is also presentable.
A second invention aspect, or special variation, is a protective shield on the holder disposed in a peripheral facial area of the second eye of the user, masking the second segment of the facial area. Advantageously, the masked sections are adjusted to one another for the quick detection of the displayed information. In this way the second passive eye is not irradiated asymmetrically with light, such that the visual impression is not disturbed and the first, active, eye can register the information quickly.
This is particularly advantageous if the contour and position of the protective shield are determined in such a way that the field of vision sections blinded by the display unit and the protective shield correspond substantially in size and position relative to the respective eye.
A further optimization is possible in that the position of the protective shield preferably designed as a black, light-absorbing aperture is adjustable, particularly in a guide, enabling an anatomical adaptation to the user. A further improvement can be achieved in that the display unit is located in a viewing axis of the first eye and the protective shield is located in a viewing axis of the second eye, and that the two viewing axes are substantially parallel to each other.
To adjust the image size suitably, it is advantageous if the display unit facing one of the observing eyes of the user comprises an optical lens unit, particularly in the form of a Fresnel lens. This can advantageously be achieved structurally in that the display unit is disposed as a structural unit with the optical lens in a casing that can be attached in a fixed manner to the holder.
To not restrict the central visual field unnecessarily and nevertheless ensure a rapid readability, it is advantageous if the display unit is disposed, preferably displaced upward, at an angle of more than 15° with respect to the central axis of the monocular visual field of the first eye.
To further improve the ergonomics, it is advantageous if the display unit, and optionally, the protective shield, are displaced on the lower surface of a, part of the holder protruding from the forehead of the user, above the eyes of said user when in use, disposed, particularly, on the visor of a headgear or on the bill of a peaked cap. As a holder, an anti-glare cap (Visor Cap) is also advantageous, consisting of a visor and an elastic head band.
Advantageously, the information is transmittable via a control unit to the display unit and is visually presented there via alphanumeric or graphic symbols, whereby the control unit is preferably connected to an external information source linked via a wireless data transmission path, such that the display itself can be constructed to be compact and light. A further improvement, also with respect to weight distribution and protection against damage, can be achieved in that the control unit is disposed on or in a part of the holder, in particular on a visor of a head covering.
To allow an ergonomic, and at the same time, a demand-mode of operation, it is advantageous if a switch unit for activating and/or switching over to the display unit is disposed on the holder.